If your building an automatic antenne switch that follows your transceiver or your building your own amplifier this building block can come in handy:
The BCD-14 decodes the band data signals from the radio or computer to automatically select the proper antenna or band pass filter for the current band.
The inputs are optically isolated to provide maximum isolation between your radio or computer and the antenna switching system.
This circuit board covers all the HF bands from 160 to 10 meters, including the WARC bands, 6M, 2M, and 440MHz !
You can find it at United Micro for +-20 Euro: